- Primary Alcohols via Nickel Pentacarboxycyclopentadienyl Diamide Catalyzed Hydrosilylation of Terminal Epoxides
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The efficient and regioselective hydrosilylation of epoxides co-catalyzed by a pentacarboxycyclopentadienyl (PCCP) diamide nickel complex and Lewis acid is reported. This method allows for the reductive opening of terminal, monosubstituted epoxides to form unbranched, primary alcohols. A range of substrates including both terminal and nonterminal epoxides are shown to work, and a mechanistic rationale is provided. This work represents the first use of a PCCP derivative as a ligand for transition-metal catalysis.
- Lambert, Tristan H.,Steiniger, Keri A.
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supporting information
p. 8013 - 8017
(2021/10/25)
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- Carbocyclization reaction of ω-iodo- and 1,ω-diiodo-1-alkynes without the loss of iodine atoms through a carbenoid-chain process
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(Chemical Equation Presented) Atom-economical carbocyclization reactions of ω-iodo-1-alkynes and 1,ω-diiodo-1-alkynes to give products with incorporation of iodine atoms is described. Cycloisomerization of 2-(2-propynyloxy)ethyl iodides is initiated by a catalytic amount of LDA to give 3-(iodomethylene)tetrahydrofurans in high yields. Upon treatment of with a catalytic amount of 1-hexynyllithium, 1ω-diiodo-1-alkynes efficiently undergo cycloisomerization to give (diiodomethylene)cycloalkanes. The diiodomethylene products are also obtained by iodine atom-transfer-type cyclization of ω-iodo-1-alkynes, using 1-iodo-1-hexyne as an external iodine atom source. Bromine atom-transfer and proton-transfer cyclization proceed as well by employing 1-bromo-1-octyne and 1-octyne, respectively. These reactions are proposed to proceed through a carbenoid-chain process involving exo-cyclization of the lithium acetylide intermediates to give Li,I-alkylidene carbenoids. It is shown that the exo-cyclization proceeded stereospecifically through inversion of the stereochemistry at the electrophilic carbon.
- Harada, Toshiro,Muramatsu, Keiko,Mizunashi, Kenia,Kitano, Chie,Imaoka, Daisuke,Fujiwara, Takayuki,Kataoka, Hiroshi
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p. 249 - 258
(2008/09/17)
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- ACETONITRILE DERIVATIVE, PEST CONTROL AGENT, AND METHOD OF USING THE SAME
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An acetonitrile derivative represented by the general formula (I): (I) (wherein A represents (VV) or (WW) B represents (XX) (YY) or (ZZ) and R represents hydrogen, C1-6 alkyl, etc. (Q1, Q2, Ar1, and Ar2 each represents phenyl, substituted phenyl, etc.; R1, R2, R3, R4, R6, R7, and R8 each represents hydrogen, C1-6 alkyl, etc.; R5 represents C1-6 alkyl, etc.; G represents NR10, etc.; W represents O, S, NR9, etc.; R9 and R10 each represents hydrogen, etc.; and n is an integer of 0-4)). The acetonitrile derivative is remarkably active in controlling pests even when used in a small dose. It is useful as an agricultural or horticultural bactericide or an animal parasite control agent.
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Page/Page column 81-82
(2010/11/08)
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- Production of oxyalkylated α-hydroxy acetylenic compounds
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Production of oxyalkylated acetylenic alcohols by reaction of acetylenic alcohols with alkylene oxides in the presence of phosphines, polar aprotic solvents or thioethers.
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